Spinal monitor apparatus and method

ABSTRACT

A method and apparatus for monitoring posture deficiencies in the spine and including a flexible body ( 30 ) encapsulating a flexible operating arm ( 31 ) cantilevered from a base moulding ( 34 ). The operating arm ( 31 ) is provided with upper ( 37 ) and lower ( 40 ) strain gauges bonded to the upper and lower faces respectively of the operating arm ( 31 ) at the point beyond the stiffening base moulding ( 34 ) to ensure that differential strain is experienced on deflection of the operating arm ( 31 ). Wire tails ( 41 ) are terminated as a PCB assembly ( 45 ) mounted to the printed circuit support ( 35 ), which assembly comprises a PC board bearing an LSI processor ( 46 ), rechargeable battery ( 47 ), vibrating motor ( 50 ) and inductive coil ( 51 ) selected to fulfil the functions of transmitting and receiving element, and inductive power supply for charging the battery ( 47 ), under the control of processor ( 46 ). The base moulding ( 34 ) is intended to be located in the region of L 4  and L 5 , the flexible body ( 30 ) and base moulding ( 34 ) being secured in place by surgical adhesive.

This invention relates to a spinal monitor apparatus and method. Thisinvention has particular application to a spinal monitor apparatus andmethod for use in diagnosis and treatment of lumbar dysfunction andtraining desirable postural habit and hereinafter this invention will bedescribed in terms of this application. However, it is envisaged that aspinal monitor apparatus and method in accordance with the presentinvention will find other applications such as on other portions of thespine, or in other applications such as encouraging good liftingpractices.

The prevention and treatment of back problems including those caused bypoor posture and poor work practices such as unsafe lifting practices isimportant economically and in terms of quality of life. The underlyingcauses of poor posture for example are many, and include acquired habitsand injury. Treatment may include surgical intervention orphysiotherapy, and the use of prostheses such as back braces or corsets.The palliative apparatus are also restrictive, uncomfortable and carrynegative social implications. Further, restriction by these means mayinterfere with nutrition of the intervertebral discs which is usuallyenhanced or encouraged by flexion in the normal range.

A further problem resides in the fact that the inter-vertebral discshave a negligible nerve supply. Therefore, under normal circumstances,they feel no pain. When a person habitually assumes incorrect posture(whether sitting, standing or lifting) damage is being done unwittinglybecause there is no pain to act as a warning of impending and cumulativedamage.

The disadvantages of the traditional palliative measures, thelimitations of physiotherapeutic treatment and the drastic nature ofsurgical intervention, have led to development of several non-invasiveposture training aids. One of the characteristics of the human spinewhich distinguishes it from the spine of most other vertebrates is thesinuous form, presenting a substantially concave lumbar region,transforming into a substantially convex dorsal presentation in thethoracic region. A key element in maintenance of good posture andameliorating or preventing injury is the maintenance of the appropriatelumbar curvature or lordosis. Several prior art apparatus-have beensuggested for this purpose.

United Kingdom Patent No. GB-2205039 (Williams) discloses an apparatusfor monitoring spinal flexion and including a casing adapted to besupported in the region of the 12th thoracic (or dorsal) vertebra andforming a first reference point and an elongate monitoring member in theform of a resilient extension extending from the casing to bear on thespine in the region of the first sacral vertebra, thus forming a secondreference point. In use, the apparatus emits a noise or vibration whenthe spatial relationship between the second reference point, resilientlybiased toward the spine, and the casing, approaches that which would beinduced when the reference points correspond to a selected loss oflumbar lordosis.

A disadvantage of the apparatus disclosed in the Williams reference isthat the two reference points utilized do not measure the loss oflordosis as such. The apparatus merely monitors the spatial relationshipbetween the two reference points. The disclosed apparatus does notmonitor and respond to changes in curvature of the spine directly orindirectly. Where the Williams apparatus does indicate loss of lumbarlordosis, it does so incidentally. With reference to the exampledisclosed at page 3, line 5 through to 7 of the Williams reference,there is reference to touching the knees and bending over, clearlyflexion type movement not directly dependent upon a change occurring inthe curvature of a particular portion of the spine.

The Williams apparatus would not detect flattening of the lumbar curveif the user is sitting upright in a chair but still slumping in thelumbar spinal region.

The lumbar curvature may be lost without inclining. This may bedemonstrated by the observation that a person may bend forward at thehip joint without flattening the lumbar curvature.

In one aspect the present invention resides broadly in a method for theprevention and treatment of posture deficiencies including the steps of:

monitoring a selected portion of a spine for functions of curvature;

producing a signal corresponding to said monitored curvature, and

using said signal to provide an indication of said curvature.

The function of curvature may be selected from the displacement ofcurvature, rate of change or velocity of curvature, or acceleration ofcurvature change.

The monitoring of the function of curvature may be continuous orintermittent monitoring. The type of signal generated by the signalmeans may take any form determined by the choice of monitoring means andsignal means, as well as the type of indication of curvature required.The functions of curvature expressed by the indicator means may forexample represent displacement of curvature, or alternatively some otherfunction such as rate of change of curvature or accelerations of thatrate.

In a further aspect this invention resides broadly in apparatus for theprevention and treatment of posture deficiencies including:

monitoring means adapted to directly or indirectly monitor the curvatureof a portion of a spine; and

signal means responsive to said monitoring means and adapted to generatea signal indicative of said curvature.

The portion of the spine may be any portion for which conditions ofadverse curvature are relevant to matters of prevention, treatment,training or maintainence of posture. Examples include the lumbar,thoracic and cervical spine. The curvature may be in the dorsal,sagittal or any other plane.

The monitoring means may be adapted to monitor the curvature of theselected portion of the spine as a continuous smooth curve oralternatively may monitor the curvature by reference to discretepositions on the spine.

However, where the monitoring of discrete positions on the spine isused, the monitoring means must monitor the actual curvature of thespine directly or indirectly, rather than from inference. Accordingly,where the monitoring means monitors the spatial relationship betweendiscrete selected locations on the spine, there must be at least threeof the selected locations to provide a first approximation of thecurvature.

The monitoring means may be adapted to monitor curvature and provide asignal dependent on the angular displacement between adjacent monitorelements of a plurality of monitor elements attached to or in contactwith the selected plurality of selected spinal locations. Alternatively,the monitoring means may include a unitary body member secured to theselected spinal region and including internal signal generating meansresponsive to the direct correspondence between the body member and thespinal curve to which it is attached.

The monitoring means may advantageously include a flexible body memberadapted to conform in use to the lumbar portion of the wearer's spine,and securing means. The securing means may also take any form consistentwith the function of maintaining the body member in position on thewearer. For example, the securing means may comprise one or more ofadhesive pads or tape members, straps or any other suitable means. Themonitoring means may for example comprise an elastomeric housing havinga surface adapted to engage the skin of the user by way of an adhesivelayer. For example, the adhesive may comprise a medical gradehypoallergenic adhesive. Preferably the securing means, and indeed thebody member and securing means in assembly, are such that they areunobtrusive to avoid embarrassment of the wearer in use. In certainembodiments of the present invention, the securing means may adjustablymount the body member to provide an element of fine-tuning to thepositioning the body member relative to the part to be monitored.

The signal means may comprise electromagnetic, electronic, optical,electromechanical, pneumatic or mechanical signal means. Preferably, themonitoring means and signal means are configured such that themechanical reaction of the apparatus to movement of the spine of theuser is minimized such that the user's awareness of the action of theapparatus is minimized. Accordingly, in the case of discrete monitoringelements, the interrelation between the adjacent elements is preferablymonitored by optical or electronic means and the signal generated isoptical, electronic via an optical coupler, or electronic asappropriate.

The signal means may only provide a signal in response to the, forexample, curvature of the spine when it exceeds certain predeterminedlimits. Accordingly, the signal means may be selected from a wide arrayof signal means including pressure, temperature, conductivity orproximity signal means. However, it is preferred that the monitoringmeans provide a continuous output across a range of positions of themonitoring means.

The signal means may include magnetic signal means such as reed switchesor inductance devices and accordingly the signal means may include abody mounted portion acting in conjunction with, for example, a magneticcomponent attached to the wearer. Alternatively, the signal means maycomprise an elongate flexible strip of metal or plastic embedded in theflexible body member and having one end adapted to interact with atransducer selected to output a signal corresponding to the curvature.In order that the signal means faithfully reflects the curvature of themonitoring means and thus the spine of the user, there may be providedsignal means comprising a metal strip embedded in the elastomeric bodyof the monitoring means and cantilevered from a relatively rigid portionthereof. A pair of strain gauge transducers may be provided on theopposed flat surfaces of the strip, which may be said to have a ventralsurface and a dorsal surface. Thus a differential signal may begenerated which corresponds to the curvature of the strip and hence thecurvature of the user's spine.

The signal generated by the signal means may interface with indicatormeans which may include any one or more of vibratory stimuli, audiostimuli, electrical stimuli or a visual indication such as screen basedoutputs or indication lights. For example, the indicating means maycomprise an aversive indication of an adverse static or dynamiccurvature and be of an unpleasant or irritating nature to reinforce themaintenance of good posture and to this end it is preferred to utilize amethod which involves vibro-tactile stimulus of sub-audible frequency.Alternatively, the indicator means may serve to signal the wearer of thecondition such that positive reinforcement of, for example, poor posturehabits may be attained. Where the user is receiving a conditionresponsive indication of adverse posture, this stimulus may be appliedimmediately or after a selected delay.

Of course, the apparatus may be so configured that both conditionresponsive and timed stimuli are supplied to the wearer, to indicatepoor posture and to stimulate the wearer periodically for voluntarypostural variety respectively. The timed stimuli of such apparatus maybe user programmable to act as an unobtrusive alarm or reminder system.The timed stimulus may take the form of a mild electric shock, thermalindication, visual indication or soft, audible indication, or any othersuitable indication. However, it is preferred that the indicator meansagain include means capable of generating a vibration to which thewearer's tactile sense can respond, the vibration preferably being ofsub-audible frequency and/or volume such that the vibration cannot bedetected by others.

The indicator means may be deactivatable to permit gathering of baselinedata on the curvature function of the patient.

The signal means may output to indicator means that may be selected frommeans of recording condition status on a continuous, intermittent orcondition responsive basis. For example, for diagnosis and treatment bya health care professional, there may be associated with the apparatus adata terminal or console unit. The console unit may be adapted toreceive data comprising a processed version of the signal from theapparatus in real time or batch mode. Alternatively the console may dealwith raw signal. The data or signal may be transmitted to the console bycable and/or wirelessly. In a wireless example, a coil may be embeddedin the apparatus and adapted to receive and transmit the modulatedsignal from the signal means via appropriate circuitry.

A power supply may be provided to power the circuitry associated withthe preferred apparatus. The power supply may be integral with the bodymember or securing means, or may be located apart therefrom andconnected by suitable wires or the like, such that the power supply maybe carried in a pocket. The power supply preferably takes the form of awireless power supply. For example the power supply may comprise aninductive coil within the monitoring means body and adapted chargerechargeable batteries therein. The inductive charging may befacilitated by a cradle mount for the monitoring means body having anelectric field generator in close proximity to the inductive coil whenthe monitoring means body is so mounted. The inductive coil may performthe alternating duties of radiating member for wireless data transferand inductive charging coil for maintenance of the batteries.

When used in a rehabilitatory role or posture training role, the consoleand/or monitor apparatus may advantageously be provided data collectionsuch as with a counter, time base record or the like adapted to recordthe number and timing of stimuli applied to the wearer by the reactingmeans. The console may form part of or be connectable to a PC for dataprocessing and statistical analysis to assist in diagnosis andtherapeutic design.

The purpose of the preferred embodiments of the present apparatus andmethod is to provide a method of monitoring in real time, and presentingfeedback to the user, data relating to their posture, as measured by thecurvature profile of their lower spine relative to an ideal or referenceposture. This may be undertaken in the static situation, typically withthe user in a sitting position, or in the dynamic situation, with theuser undertaking activities ranging from normal day-to-day tasks throughto heavy lifting or exercise conditions.

In operation, the preferred apparatus performs a number of specificfunctions of benefit to the user, including:

(a) postural training, wherein warning the user that their posture hasdeviated from the ideal reference by a pre-set degree over a pre-setperiod of time, makes the user aware of the need for postural correctionto avoid long-term spinal damage, or the aggravation of a pre-existingcondition. Postural training also conditions the postural supportmuscles and the brain's motor control of these muscles;

(b) postural monitoring, wherein recording over a period of time theuser's posture relative to the ideal reference posture and making therecorded data available for analysis by trained personnel, the systemallows user behavior which may threaten the health of the spine to bedetected and corrected. Faulty equipment such as seating or workstationsthe use of which may threaten the health of the spine may also bedetected and replaced of reconfigured; and/or

(c) preventative training, wherein the knowledge that spinal conditionscan result from and be aggravated by persistent periods of posturalmonotony is used in monitoring activity and warning the user of periodsof postural monotony which exceed a predetermined elapsed time, suchthat a certain minimum level of postural variety can be achieved,thereby minimising the risk of this phenomenon.

To achieve these ends the apparatus may be operated in various modes.For example, there may be defined a sitting mode and a lifting mode:These may be pre-set combinations of parameters. The sensitivity of theapparatus and the regimes applies may be variable. For example there maybe 3 levels of sensitivity in the sitting mode and in the lifting mode.The user may be able to adjust the underlying values behind thesensitivities (i.e. the levels) but when the product is shipped, thelevel 1 may be the ‘easiest’ level (i.e. sensitivity), level 2 may beintermediate and level 3 may be advanced. In other words, level 1 mayallow the greatest range of movement before the limits are transgressed,and level 3 may be the smallest (and therefore most difficult) range.

The apparatus may be provided with varying access levels such as normaluser access, researcher access, and developer access. Normal user accessmay be the product's normal access level. Researcher access may allowthe user to change the underlying values behind the preset levels whilstabsolute values are not revealed—only relative values from the neutral(central) posture. Developer access also allows the underlying values tobe changed, but absolute values are displayed, not relative values.

The range of allowable movement within any Level (sensitivity) is notnecessarily symmetrical in each direction in the sagittal plane. Forexample, when the user begins a posture training Session (whereby theyreceive feedback when their posture goes outside of the desired range),they assume the ideal ‘neutral’ spinal posture and then press the trainkey on the console (or it could be on the sensor itself). Pressing thetrain key enters/logs the neutral posture, around which the allowablerange will be calculated. The amount of movement allowed in the flexion(forward-bending) direction is usually more than is allowed in theextension (lumbar-arching) direction. The point is that the range ofallowable flexion and extension is not necessarily symmetrical eitherside of the neutral spinal position. Also, these flexion and extensionlimits can be adjusted either semi-automatically by choosing a differentsensitivity level or manually via the researcher access function.

Preferably, the apparatus and method is not used to provide stringentposture training for many hours on end. A most stringent form oftraining provided by the apparatus is preferably set in the apparatus,where the user must stay within the desired posture range if a posturetransgression is to be avoided. Such a posture training session maybegin by (a) the wearer assuming the ideal neutral posture (be that insitting or standing), and then (b) pressing the train key. Pressing thetrain key may for example do three things: (1) log the neutral posturefor that posture training session, (2) log the date and start time ofthe posture training session, and (3) begin the countdown timer thatwill automatically end the posture training session after the allottedtime. This may be 5 minutes, 15 minutes, 60 minutes or any perioddesired—i.e. it is user-defined and variable. This auto-dosage functionmay help avoid over-training with the apparatus.

The apparatus and method of the present invention lends itself to threedistinctly different forms of training: (1) Static posture maintenance,(2) Avoidance of end-range postures, and (3) Avoidance of spinalimmobility. Static posture maintenance refers to the posture trainingsessions whereby the user tries to stay within the prescribed posturerange for the duration of the posture training session. During posturetraining sessions the “out of ideal posture range” feedback is emittedimmediately or with only a very small delay (in the order of a fewseconds).

Avoidance of end-range postures (e.g. slumping whereby the person'sspinal joints ‘hang’ on their ligaments, thus stretching and damagingthem and therefore contributing to the instability and vulnerability oftheir spine) also involves notifying the wearer when their posture isoutside of the desired range, but the feedback is not immediate—it isdelayed in the order of minutes; e.g. 1 to 15 minutes. This delayedfeedback does not condition the muscles' motor control ability as doesmore immediate feedback. Instead, the purpose of the delayed feedback issimply to remind the wearer to get out of end-range postures after anumber of consecutive minutes of being outside of the ideal posturerange. This aims to develop the habit of returning to the neutral rangemomentarily on a frequent basis throughout the day.

Avoidance of spinal immobility refers to the time-based ‘stretch break’reminders. These have a different objective to (2) above. Instead ofencouraging the user to briefly return to the neutral range, the stretchbreak reminders encourage the user to gently move through their fullrange of motion in all planes-sagittal, lateral and torsional.

The invention will hereinafter be further described with reference to apreferred embodiment thereof as illustrated in the accompanying Figures,wherein:

FIG. 1 is a diagrammatic view of an apparatus and method of the presentinvention;

FIG. 2 is a diagrammatic view of a monitoring apparatus suitable for usein the apparatus and method of FIG. 1;

FIG. 3 is a diagrammatic view of the principle of operation of themonitoring apparatus of FIG. 2;

FIG. 4 is a diagrammatic view of a console suitable for use in theapparatus and method of FIG. 1;

FIG. 5 is a diagrammatic view of system configurations of the apparatusand methods of FIGS. 1 to 4;

FIGS. 6 to 9 are a flow chart of software functions of apparatus inaccordance with the present invention;

FIG. 10 is an exploded three-quarter perspective view of a monitoringapparatus suitable for use in the present invention;

FIG. 11 is a plan view of the monitoring apparatus of FIG. 10, with topcover removed;

FIG. 12 is an exploded section view of the monitoring apparatus of FIGS.10 and 11;

FIG. 13 is a plan view of the monitoring apparatus of FIGS. 10 to 12;

FIG. 14 is a side view of the monitoring apparatus of FIGS. 10 to 13;

FIG. 15 is a side section view of the monitoring apparatus of FIGS. 10to 14;

FIG. 16 is a side section detail view of the monitoring apparatus ofFIGS. 10 to 15;

FIG. 17 is a representation of a single monitoring apparatus system inaccordance with the present invention;

FIG. 18 is a representation of a multiple monitoring apparatus system inaccordance with the present invention;

FIG. 19 is a diagram illustrating spinal movement modes; and

FIGS. 20 to 22 are plan, side and end views respectively of a monitoringapparatus arrangement suitable for use in monitoring multiple modes ofspinal movement.

The present embodiment consists of three main elements, plus a number ofancillary items. With reference to FIG. 1, the main elements include amonitoring apparatus which is attached to the user's lower spine usingmedical adhesive tape, and performs the function of periodicallymonitoring spinal curvature by measuring the front-to-back displacementof the vertebra relative to a reference point formed at the junction ofthe L4 and L5 vertebrae. Displacement is measured by using an elasticcantilever to translate front-to-back movement to a force proportionalto the displacement, the force being measured by a force sensor. Theconfiguration enables measurement of both forward movement (arching-orextension) and backwards movement (slumping or flexion) of the lumbarspine. The spinal curvature estimate is processed by the monitoringapparatus to allow warnings to be given to the user; stored in themonitoring apparatus for later retrieval, and conveyed via a wirelesscommunications link to the console for further processing, presentationto the user and storage for later analysis. The monitoring apparatus ispowered by a battery which may be recharged from a main derived source,via a contactless power transfer mechanism with the console.

A console may be used either free standing in the vicinity of the user,or may be placed in a pocket, handbag or attached to the user's belt.The console communicates with the monitoring apparatus via a wirelesscommunications link to establish the monitoring apparatus configurationand operating parameters, and to retrieve spinal curvature estimatesfrom the monitoring apparatus for display to the user via a liquidcrystal display (LCD). The user may control the console and thence thepad via the console keypad. The console additionally provides facilitiesfor the upload of stored data to a personal computer (PC) which hostsanalysis software for the analysis and presentation of recorded data Abattery that may be recharged from a mains derived source, via a contactconnection, powers the console.

Analysis software consists of a suite of custom software operating on astandard PC, used to retrieve data from the console via a cable based orinfra-red connection, and the storage, analysis and presentation to theuser of that data. This facility assists in the diagnosis of userbehavior which is contributing to spinal damage, and may also be used totrace aberrant behavior, for example, leading to a workplace injury.

Other features include cradles for housing various combinations ofmonitoring apparatus and console, depending on system configuration, forrecharging the batteries in these the monitoring apparatus is describedin the following section, with reference to the block diagram of FIG. 2.

In use, the monitoring apparatus is firmly attached to the user's spineusing medical adhesive tape. Normally, the reference surface formed bythe lower edge of the rigid base of the monitoring apparatus body isattached at the junction of the L4 and L5 vertebrae, with the uppersection of the monitoring apparatus body which forms the cantileverattached to the vertebrae immediately above the L4 vertebra. Themonitoring apparatus may be attached at other locations on the spine,with an appropriate adjustment made to measurement calibrationparameters and set points.

By a method described in more detail hereinafter, the sensing padproduces a voltage output that is related to the curvature of the user'sspine by a non-linear but repeatable characteristic. This voltage isperiodically sampled and converted to a digital value by an analogue todigital converter that forms a part of the microcontroller. A lookuptable stored in the non-volatile memory is used to convert the digitalrepresentation of the sampled value to a linearised value that isproportional to spinal curvature, with a fixed constant ofproportionality. The lookup table also performs the function ofcorrecting unit to unit variations in sensing pad characteristics thatresult from differences during manufacture, so that the spinal curvatureestimate is consistent between monitoring apparatus units. Thiscorrection is achieved as a part of a calibration process undertakenduring monitoring apparatus manufacture. Spinal curvature sampleestimates are measured at frequent intervals, typically up to 4 timesper second, or at a lower rate depending on the operating mode.Depending on the monitoring apparatus operating mode, the data may beprocessed in a number of ways.

In an operating mode where the monitoring apparatus is operated in astand-alone mode, hereinafter referred to as “sensor autonomous mode”,spinal curvature estimates may be processed by the microcontroller,using an algorithm which determines whether the user should be warned ofbad posture. Using operating parameters and set points downloaded to themonitoring apparatus from the console during the monitoring apparatussetup procedure, the algorithm determines when the conditions for awarning to be delivered to the user have been satisfied, and alerts theuser via a vibration generated under microcontroller control via thevibrating motor. The monitoring apparatus is thus operating autonomouslyduring the period where the user is wearing the monitoring apparatus inthis mode. The algorithm takes into account the degree of spinalcurvature from a reference position established during set-up, thenumber of transgressions which have occurred during a time period, andthe number of warnings given to the user over a period of time, and theduration of the transgression. A number of settings of these parametersare provided for, to allow for the skill and experience of the user inusing the system, and the severity of the condition being monitored.That is, the strictness of the training can be varied.

When the optional high capacity non-volatile memory and optionalreal-time clock (RTC) are fitted, spinal curvature sample data is timestamped with time information read from the real-time clock, and storedin the monitoring apparatus non-volatile memory, for later retrieval bythe console and subsequent uploading to the PC for processing.

When the monitoring apparatus is operating in conjunction with aconsole, spinal curvature estimates are periodically uploaded to theconsole, typically at a rate lower than the sampling rate, with theoption of a number of samples being preprocessed by the monitoringapparatus prior to uploading (e.g. by averaging several samples). Inthis configuration, the algorithm that determines when the conditionsfor a warning to be delivered to the user have been satisfied, isimplemented by the console which also displays a range of informationrelating to user activity. When the transgression alert is required, theconsole conveys the appropriate command to the monitoring apparatus,which in turn alerts the user via a vibration generated undermicrocontroller control via the vibrating motor. Time-stamped spinalcurvature sample data is stored in the console non-volatile memory, forlater uploading to the PC for processing This mode of operation isparticularly useful during user training, or intensive monitoring of auser by a trained operator.

The monitoring apparatus undertakes bi-directional communications withthe console via a wireless bidirectional link, implemented usingmagnetically coupled communications between a coil located in themonitoring apparatus, and corresponding coil (or optionally, two coilsmounted with axes orthogonal) in the console. Amplitude modulation of alow frequency radio frequency carrier at frequencies typically in thevicinity of 50 kHz to 100 kHz is used to convey information between themonitoring apparatus and console. A master/slave poll-response messageexchange strategy is used, with the monitoring apparatus normally actingas master (although the console can act as master during monitoringapparatus set-up or other operating modes). Each monitoring apparatushas a unique identity, which is used by the console and monitoringapparatus associated with that console to allow communications betweenthat pair of units, and to ignore signals from other non-associatedunits which may be operating in the vicinity.

With reference to FIG. 2, a local oscillator signal at the transmissionfrequency is generated by the microcontroller is connected to thesignalling transmitter, and amplitude modulated by on/off switching bythe TX modulator in accordance with the logic state on the TX datasignal. Messages to be transmitted from the monitoring apparatus to theconsole over ranges typically up to 1 metre are encoded with framing andchecksum protection information, and are encoded to guarantee anadequate density of transitions to allow effective bit timing recoveryin the corresponding receiver. After amplification, the transmit signalis applied to the transmit winding of the receive/transmit coil.

Signalling messages received by the monitoring apparatus are coupledfrom the receive winding of the RX/TX coil to the signalling receiver,whence they are amplified and mixed down to an intermediate frequency(IF) by mixing with an offset local oscillator and then filtered. TheMicrocontroller then samples the resultant RX data signal which ismodulated at the IF using I and Q sampling, via an analogue to digitalconverter contained with in the microcontroller. A processing algorithmimplemented in microcontroller firmware is used to regenerate thetransmitted modulating signal, which is further processed to implementbit timing recovery, message framing and checksum checking.

In difficult communications situations, frequency diversity is used toavoid narrowband interference from devices such as computer screens. Ifcommunications cannot be established on one of a number of operatingfrequencies, alternative frequencies will be automatically tried in turnuntil reliable communications is established.

The monitoring apparatus is powered by a rechargeable battery, which ischarged by a magnetically coupled radio frequency signal derived fromthe console, or a charging adapter used specifically for the purpose. Inthe battery charging mode, the monitoring apparatus is intimatelycoupled with the console by locating the monitoring apparatus in areceptacle provided on the console for the purpose. In alternativeconfigurations the coupling is achieved between the console andmonitoring apparatus by locating bath in an adapter provided for thepurpose; or the monitoring apparatus is placed into the charging adapterwhich provides the charging signal.

With reference to FIG. 2, in the battery charging configuration thecharging signal is coupled from the battery charging winding on thereceive/transmit coil, to the battery charging control, which is enabledby the microcontroller when battery charging is required. When chargingis enabled, received charging energy is rectified and applied to thebattery. If charging is not required or has been completed, themicrocontroller will disable battery charging, which can be sensed bythe console due to the resultant change in impedance seen by its powersignal transmitter, allowing the console in turn to deactivate charging.The microcontroller monitors charging via the monitor signal connectedto an analogue to digital converter internal to the microcontroller.When the battery is depleted to the extent that insufficient voltage isavailable to operate the microcontroller, the enable signal is arrangedto become active, to ensure that battery charging will occur tosubsequently allow the monitoring apparatus to become active.

The battery provides the operating voltage to the microcontroller andother functional blocks, including the voltage reference which generatesstable reference voltages required by other monitoring apparatusfunctional modules.

All functions of the monitoring apparatus are controlled by operatingfirmware hosted by the microcontroller. The microcontroller isimplemented by a single chip 8-bit microcontroller with built inanalogue to digital converter channels, and which is available inone-time programmable or mask programmable form. The clock signalrequired for normal microcontroller operation is provided by themicrocontroller oscillator consisting of a ceramic resonator. Themicrocontroller reset circuit monitors battery voltage, and resets themicrocontroller whenever inadequate supply voltage is available. Themicrocontroller includes an internal watchdog reset circuit which resetsprogram operation in the event of failure of normal operation.

In order to minimise the current drawn from the monitoring apparatusbattery and hence maximise the time between re-charges, themicrocontroller incorporates measures to ensure that the low-currentIdle state of operation is adopted for as great an amount of time aspossible. When a user monitoring or training session is not in progress,the monitoring apparatus remains idle for the majority of the time,activating only periodically to sense for signalling messages from aconsole which indicate that the monitoring apparatus should becomeactive to receive instructions from the console.

The monitoring apparatus may be equipped with an optional pushbuttonswitch and speaker. The pushbutton may be used to activate anddeactivate the monitoring apparatus; to place the monitoring apparatusin a condition where it attempts to establish communications with aconsole for association, setup and data upload functions, and toinitiate or terminate training and monitoring sessions. The optionalspeaker is used in conjunction with the pushbutton to provide feedbackto the user when pushbutton functions are being implemented. Themonitoring apparatus is configured as a fully sealed unit, withoutexternal electrical connections, to minimise problems encounteredthrough contact with body fluids and cleaning fluids.

The function of the monitoring apparatus is to provide an estimate ofthe curvature of the spine, relative to a reference position establishedat the commencement of each training or monitoring session Themeasurement method is explained with reference to FIG. 3 which is drawnin exaggerated scale for clarity. The analysis presented below issimplistic in that the distributed nature of applied forces is not takeninto account; rather, moments about the pivot point are considered interms of the equivalent point force operating at a prescribed distancefrom the pivot point, equivalent to the integrated moment about thepivot point resulting from the distributed force which the point forcerepresents. Additionally, second order and nonlinear effects are notconsidered in the analysis.

The sensing pad provides a measurement of spinal displacement in thehorizontal plane at vertebrae immediately above vertebra L4, relative toan axis formed by vertebra L4 and L5, and hence provides an estimate ofthe curvature of the lower spine. Displacement of the spine at the endof the cantilever furthest from the pivot point is denoted as Ds forslump (ie forward bending) and Da for arch (ie backwards bending).Assuming linear mechanical operation, the cantilever of spring constantK will require net forces at the far end of the cantilever of Fs=KDs tocause slump displacement Ds, and Fa=KDa to cause arch displacement Da.

Displacements Ds and Da are sensed by force sensor, coupled to thecantilever by a coupling pad which absorbs any longitudinal movement (iesliding) and thus prevents wear of the force sensor. The force sensorresistance changes with the total force applied to the sensor activearea, this resistance change being converted to a voltage measured bythe microcontroller analogue to digital converter, by current flowingthrough the force sensor.

The nature of the force sensor is that it is able to measure onlypositive forces applied to it, requiring the coupling pad to maintaincontinuous contact with the force sensor. This is achieved in practiceby applying a pre-load force Fp to the cantilever, to ensure that formaximum arch condition Fa, the force Fm applied to the force sensorremains positive.

With reference to FIG. 3, the force equations relating measured force Fmto Ds for slump and Da for arch are readily apparent.

Non-linearities and unit to unit variations resulting from thecharacteristics of the force sensor, the materials used and second ordereffects can be readily compensated by the use of a calibration procedureduring manufacture, with a calibration lookup table being stored inmonitoring apparatus non-volatile memory. If necessary, re-calibrationduring the life of the monitoring apparatus can be achieved by updatingthe calibration lookup table.

For reliable and repeatable operation, it is important that themonitoring apparatus mechanics and the force sensor be designed to avoidwear, hysteresis effects or changed of characteristics with temperature,humidity, atmospheric pressure and age.

The console is described in the following section, with reference to theblock diagram of FIG. 4. In use, the console is located either freestanding on a convenient surface, or in a purse, pocket or attached tothe user's belt To effect an interface the console must be locatedwithin radio range of the monitoring apparatus, typically up to 1 metre.During programming and monitoring operations, the console must belocated so that the user may view its display. Additionally, duringprogramming, its keypad is operated by the user. During communicationswith the PC, the console is located in an interface adapter and thenceconnected to the PC interface.

When the console is operating in conjunction with a monitoringapparatus, the console communicates with the monitoring apparatus toupload spinal curvature estimates, which are processed, stored,displayed to the user. When required, the console conveys a command tothe monitoring apparatus to deliver a warning to the user. This methodof operation is described fully in the section above dealing withmonitoring apparatus operation.

Spinal curvature data received from the monitoring apparatus is date andtime-stamped with time information from the real-time clock, and storedin the console non-volatile memory, for subsequent uploading to the PCfor processing.

When the monitoring apparatus is to be used in autonomous mode, theconsole is used to set up the configuration required for the training ormonitoring activity, and download these settings to the monitoringapparatus. On completion of the training or monitoring activity,communications is established between the console and monitoringapparatus, and data gathered during the activity uploaded to the consolefor processing, display to the user and subsequent uploading to the PC.

The console undertakes bidirectional communications with the monitoringapparatus via a wireless bi-directional link, implemented usingmagnetically coupled communications between one and optionally a secondcoil, and the corresponding coil in the monitoring apparatus. Two coilslocated with axes orthogonal to one another are provided to allowreliable communications to be established with a range of relativeangular orientations between the console and monitoring apparatus.

With reference to FIG. 4, a local oscillator signal at the transmissionfrequency is generated by the microcontroller, connected to thesignalling transmitter, and amplitude modulated by on/off switching bythe TX modulator in accordance with the logic state on the TX datasignal. After amplification by the one of the two amplifiers activatedby the n.TX1/TX2 signal, the transmit signal is applied to the transmitwinding of either receive/transmit Coil 1 or receive/transmit Coil 2.

Signalling messages received by the console are coupled from the receivewinding of RX/TX coil 1 and RX/TX coil 2, to the signalling receiver,whence they are amplified by one of the two amplifiers enabled by then.RX1/RX2 signal, mixed with an offset local oscillator and thenfiltered. The microcontroller then samples the resultant RX data signalwhich is modulated at the IF using I and Q sampling, via an analogue todigital converter contained with in the microcontroller. A processingalgorithm implemented in microcontroller firmware is used to regeneratethe transmit modulating signal, which is further processed to implementbit timing recovery, message framing and checksum checking.

In difficult communications situations, frequency diversity may be usedto avoid narrowband interference from devices such as computer screens.If communications cannot be established on one of a number of operatingfrequencies, alternative frequencies may be automatically tried in turnuntil reliable communications is established.

The console may be powered by a rechargeable battery, which is chargedby an external mains derived source electrically connected eitherdirectly to the console, or in alternative configurations via aninterface adapter.

With reference to FIG. 4, in the battery charging configuration themains derived power source is connected to the battery charging control,which is enabled by the microcontroller when battery charging isrequired. When charging is enabled, received charging energy isrectified and applied to the battery. If charging is not required or hasbeen completed, the microcontroller will disable battery charging. Themicrocontroller monitors charging via the monitor signal connected to ananalogue to digital converter internal to the microcontroller. When thebattery is depleted to the extent that insufficient voltage is availableto operate the microcontroller, the enable signal is arranged to becomeactive, to ensure that battery charging will occur to subsequently allowthe monitoring apparatus to become active.

The battery provides the operating voltage to the microcontroller andother functional blocks, including the voltage reference which generatesstable reference voltages required by other monitoring apparatusfunctional modules.

Additionally in the battery charging mode, a monitoring apparatus may beintimately coupled with the console by locating the monitoring apparatusin a receptacle provided on the console for the purpose. In alternativeconfigurations the coupling is achieved between the console andmonitoring apparatus by locating both in an adapter provided for thepurpose, or the monitoring apparatus is placed into the charging adapterwhich provides the charging signal. Via its signalling transmitter andRX/TX coil 1, the console is able to provide energy to recharge themonitoring apparatus battery. By measuring the impedance presented toRX/TX coil 1, the console is able to determine when monitoring apparatuscharging has been disabled by the monitoring apparatus microcontroller,deactivate the charging function and notify the user via the consoledisplay.

All functions of the console are controlled by operating firmware hostedby the microcontroller. The microcontroller is implemented by a singlechip 8 bit microcontroller with built in analogue to digital converterchannels, and which is available in one-time programmable or maskprogrammable form. The clock signal required for normal microcontrolleroperation is provided by the microcontroller oscillator consisting of aceramic resonator. The microcontroller reset circuit monitors batteryvoltage, and resets the microcontroller whenever inadequate supplyvoltage is available. The microcontroller includes an internal watchdogreset circuit which resets program operation in the event of failure ofnormal operation.

In order to minimise the current drawn from the console battery andhence maximise the time between re-charges, the microcontrollerincorporates measures to ensure that the low-current Idle state ofoperation is adopted for as great an amount of time as possible. When auser monitoring or training session is not in progress, the consoleremains idle until activated by a keystroke by the user. On completionof the session, the console returns to the idle condition.

The console may be equipped with a user display driver and user displayfor the presentation of information to the user, including data requiredto configure the monitoring apparatus, and information gathered duringtraining and monitoring sessions.

The console is equipped with a keypad for general control and userinterface functions, and speaker to provide feedback to the user whenkeypad and other functions are being implemented.

The console is equipped with an electrically connected serial interfacefor connection to a PC for the uploading of time-stamped data gatheredduring training or monitoring sessions. The connection to the PC is madevia an interface adapter, which may provide a direct electricalconnection between the console and PC for RS-232 connections, or signalprocessing for connection by other standard means such as universalserial bus or infra-red connection.

Data exchange between the console and PC is via a message based protocolemploying checksum protection and retransmission capability to ensureerror free data transfer.

The software on the preferred PC console based system is the subject ofthe flow chart comprising FIGS. 6 to 9. The objective of the software isto facilitate detailed analysis of the data collected by the apparatusin order to monitor a patient's posture improvement progress and todetect activities of daily living and lifestyle habits that may beincreasing the patients' risk of back injury or recurrence of back pain.The software is also used to keep case management records and patientcommunication functions.

The plug pack provides a rectified and filtered DC supply derived from astandard mains source, to provide power to system elements duringbattery charging. The console may also be operated from the mainsderived power source. The monitoring apparatus charger provides batterycharging energy to a monitoring apparatus in a manner similar to theconsole, when a monitoring apparatus is to be recharged. Operation issimilar to the monitoring apparatus battery charging function of theconsole. The monitoring apparatus charger charging bay locates themonitoring apparatus in the correct orientation for battery charging,but makes no physical electrical contact to the monitoring apparatus, inthat inductive coupling or RF charging is used.

The interface adapter and charger provides mains-derived power from theplug pack to the console, via an electrical connection from the adapterto the console. This power source is used to power the console, rechargethe console battery and when a monitoring apparatus is coupled to theconsole, recharge the monitoring apparatus battery via wirelesscoupling. Electrical connections are also provided to the console forconnection to the PC.

The multi-monitoring apparatus interface adapter and charger providesmains-derived power from the plug pack to the console, via an electricalconnection form the adapter to the console. This power is used to powerthe console, recharge the console battery and when a monitoringapparatus is coupled to the console, recharge the monitoring apparatusbattery via wireless coupling Additionally, the multi-monitoringapparatus interface adapter and charger provides battery charging energyto additional monitoring apparatus in a manner similar to the console,when a monitoring apparatus used in the multi-monitoring apparatusconfiguration are to be recharged. Operation is similar to themonitoring apparatus battery charging function of the console.Electrical connections are also provided to the console for connectionto the PC.

With reference to FIG. 5, the present system, may be used in a number ofsystem configurations. Each configuration is depicted as set up forbattery charging, to allow the incorporated elements to be clearlydetermined.

The standard console/monitoring apparatus system involves the provisionto the user of a single console and monitoring apparatus, along with aplug pack for console and monitoring apparatus battery charging. Themonitoring apparatus is typically used in conjunction with the console,although the monitoring apparatus may be used in the stand-alone mode,for example when the monitoring apparatus attached to the user modes outof communications range of the console.

The console/monitoring apparatus PC interface system operates in asimilar fashion to the standard configuration, with the addition of theinterface adapter and charger which allows the console to be connectedto the PC for data upload and analysis. The stand alone monitoringapparatus system in FIG. 18 involves the provision to the user of asingle monitoring apparatus, along with a plug pack 173 and monitoringapparatus charger 174 for monitoring apparatus battery charging. Themonitoring apparatus is pre-programmed to suit user requirements,typically using a console possessed by a practitioner. The monitoringapparatus is used in the stand-alone mode, and may subsequently bereturned to the practitioner for data upload and reprogramming.

The console/multi-monitoring apparatus PC interface system operates in asimilar fashion to the console/monitoring apparatus PC interface system,with the provision of charging facilities for additional monitoringapparatus. This configuration is useful in an environment where a numberof users are directed by a practitioner in an environment such as aclinic.

With reference to FIGS. 10 and 11, these are a front view and rear viewof a console unit 10 in accordance with the present invention, whereinthere is provided a moulded plastic case 11 having a battery compartment12 provided at its lower rear portion and adapted to conceal threerechargeable NiMH batteries 13. Docking protection is provided by heelfitting 14, which is designed to complement corner protectors 15. Thebattery compartment 12 is covered by a moulded lid 16 secured by a latch17. Facing the rear of the device and located at the sides arerecharging and data ports 20. The front of the case 11 is provided withan aperture to receive a display assembly 21 which mounts an LCD display22. The front face of the case 11 also includes apertures for threefunction keys 23 and a power key 24.

With reference to FIGS. 12 to 16, there is provided a monitoringapparatus unit comprising a moulded flexible body 30 substantiallyencapsulating a flexible stainless steel operating arm 31. The operatingarm 31 is formed of 0.3 mm material and is provided with a plurality ofapertures 32 for support during the moulding process and to allow themoulded material to migrate throughout the mould.

The rear end 33 is cantilevered from a substantially rigid base moulding34 secured to the flexible body 30 at its rear portion. A printedcircuit support 35 also functions to secure the operating arm 31 to thebase moulding 34 by means of PC board mounting screw 36 and clamp screws38 and form a cantilever chassis for the operating arm 31. The operatingarm 31 is provided with a upper 37 and lower strain gauges bonded to theupper and lower faces respectively of the operating arm 31 at the pointbeyond the stiffening base moulding 34 to ensure that differentialstrain is experience on deflection of the operating arm 31.

Respective pairs of lead-in wires 41 lead from the strain gauges 37, 40through respective moulded-in wire blocks 42 that are profiled to engageand be secured by the flexible body 30 during the moulding process. Thematerial of the flexible body 30 is displaced at 43 to accommodate thestrain gauges, which are encapsulated in a resin mass 44. The wire tails41 are terminated as a PCB assembly 45 mounted to the printed circuitsupport 35, which assembly comprises a PC board bearing an LSI processor46, rechargeable battery 47, vibrating motor and inductive coil 51. ThePCB assembly 45 is secured against some vibration from the vibratingmotor 50 in use by means of the motor being supported on a motor support52 provided on the base moulding 34.

The inductive coil 51 is selected to fulfil the functions oftransmitting and receiving element, and inductive power supply forcharging the battery 47, under the control of the processor 46.

A top moulding 53 is provided with means to snap on over the basemoulding 34 to enclose the PC board assembly 45, wherefore it may beultrasonically welded in place to environment-proof the apparatus.

The base moulding 34 is in use intended to be located in the region ofL4 and L5, the flexible body 30 and base moulding 34 being secured inplace by surgical adhesive. Since the operating arm 31 is substantiallyflat before use, the first installation provides, a positive input fromthe strain gauges 37, 40 against which the apparatus may be calibratedto baseline.

Operating modes of apparatus in accordance with the present inventionare broadly described with reference to the illustrations of FIGS. 17and 18, which in both cases illustrate the monitoring of a user 150engaged in a variety of spinal configurations in sitting and lifting. InFIG. 17, a single monitoring apparatus 160 is paired to a single console161. The monitoring apparatus 160 and console 161 are in communicationvia wireless waves 162 in use and for programming of the monitoringapparatus. The monitoring apparatus, when out of range of the console161 operates in monitoring apparatus autonomous mode to continue theprogram. The console 161 is configured to receive the monitoringapparatus 160 for wireless charging of the monitoring apparatus 160 aswell as being a convenient position for the monitoring apparatus forprogramming and stored data collection as at 164 as well as fortransport and storage as at 165 A desk stand 163 is provided on the rearof the console 161. A charger 166 is supplied for the console 161, andby wireless therefrom to the monitoring apparatus 160. A data interfacemodule 167 connects the console 161 to a PC 170 at the therapist'spremises for base programming and data collection.

In the system illustrated in FIG. 18, multiple monitoring apparatusunits 171 are associated with a single console 172 such as may be thecase where a single therapist is monitoring several patients. Themonitoring apparatus again communicate wirelessly with the console 172when in-surgery and operate in monitoring apparatus autonomous mode whenthe patient leaves. The patient is provided with an individual charger173 and desk stand 174 for home charging of the apparatus. The therapistis provided with a combined charger/data uptake module 175, wherein theconsole 172 and a monitoring apparatus 171 not with the patient may becharged, and whereby the apparatus may be configured, calibrated and/oranalyzed by a PC.

Apparatus in accordance with the above described embodiment may alsoinclude a conditioned response feedback method to condition the muscleswhich stabilizes the spine thereby preventing or treating poor posture.Since no external or prosthetic physical support is provided, theapparatus makes the muscles provide the support for the spine therebystrengthening the muscles. The silent vibratory stimulus emitted by theapparatus onto the surface of the skin of the wearer is mildlyunpleasant, thus reinforcing the conditioned response.

Accordingly, apparatus in accordance with the above embodiment does notsimply encourage a straight back, but rather a fit and healthy back.

This particular embodiment was also provided with means to issue avibration at selectable predetermined intervals, for example, everythirty (30) minutes in a distinct stimulus pattern as a reminderindicating that the wearer should bend and stretch gently and briefly toaid nutrition of the intervertebral discs. Alternatively, the apparatusmay detect the period of postural monotony in lieu of the time base perse.

Apparatus of the abovedescribed kind is neither physically nor sociallyinhibiting since nothing can be seen or heard by others. It does notinterfere with clothing and it allows the normal range of movement, forexample, the wearer can bend over if necessary to tie shoelaces, pick upobjects and the like.

In the alternative monitoring apparatus embodiment illustrated in FIGS.19 to 22, FIG. 19 illustrates the different modes of spinal movement forwhich the alternative monitoring apparatus may be applied, wherein thespine 100 is symbolically represented in side view and rear viewrespectively. In the rear view, sideways displacements are termedlateral and are indicated by the arrow at 101. In the side view,movements from to back are termed sagittal and are indicated by thearrows 102. Rotations about the general spinal axis are termed axial andapply equally to both views, being indicated in the rear view by thearrows at 103. The displacements are relative to an arbitrary fixedpoint 104.

The monitoring apparatus unit if FIG. 3 is in these terms a sagittalplane monitoring apparatus. The embodiment of FIGS. 20 to 22 describes amonitoring apparatus enabling additional measurements to be made ofaxial and lateral displacements of the spine. In the figures there isprovided a monitoring apparatus assembly 105 comprising a backing plate106 adapted to be attached to the spinal vertebrae at L4 and L5 andmounting a flexible cantilever 107 via a transverse pivot 110, aresilient rotational coupling 111 and resilient lateral couplings 112.The cantilever 107 is adapted to be secured to the skin of the user atits outer end by an attachment point 113. The movement of the cantilever107 about the pivot 110 in sagittal movement and about the resilientrotational coupling 111 causes the cantilever to interact with a pair offorce sensors 114,115 with forces F1 and F2 respectively. The lateralmovement results in displacement of the cantilever on the resilientlateral couplings 112, causing interaction with a pair of force sensors116 and 117 with forces F3 and F4 respectively, the sensors 116 and 117being mounted on respective supports 120 on the backing plate 106.

Measurement of the forces F1, F2, F3 and F4 enables sensible data to beobtained in respect of lateral, sagittal and axial motion of the spineas translated through the cantilever 107. The.sagittal force Fs which isproportional to sagittal displacement may be expressed as:

Fs=(F 1+F 2)−Fp,

where Fp is a fixed preload force to ensure that the forces applies tothe sensors 114 and 115 are always positive.

The axial force Fa which is proportional to the axial displacement ofthe spine may be expressed as:

Fa=(F 1−F 2),

where the sign of Fa determines whether the axial displacement of thespine is in the clockwise or anticlockwise direction. The differentialforces applied to the sensors 114 and 115 arises out of torsionaldistortion of the resilient cantilever 107.

The lateral force F1 which is proportional to the lateral displacementof the spine may be expressed as:

F 1=(F 4−F 3),

where the sign of F1 determines lateral displacement of the spine to theleft or right. Lateral spinal displacements result in rotation of thecantilever about the axis of the rotational coupling 111, causing achange in forces applied to the force sensors 116 and 117. The resilientcouplings 112 are preloaded such that the force on the sensors 116 and117 are always positive.

Whilst the first order equations above represent the dominant effects ofthe respective displacements on the sensors, in practice lower ordereffects will arise out of the complex interplay of characteristics ofthe cantilever, the rotational and flexible couplings, the flexibilityof the user's skin and underlying tissues. Outputs varying from firstorder may be to some degree normalized by calibration.

Whilst apparatus is described with reference to the problems occurringin the lumbar region of the spine, the apparatus is in principle,equally applicable to the cervical and upper thoracic regions of thespine as well as in lateral curvature conditions such as scoliosis androtations.

It is envisaged that the apparatus of the foregoing embodiments may beoperable in various combinations and product specifications toaccommodate differing technical requirements and markets. Forconvenience these are referred to as distinguishing marks. Mark Iapparatus may comprise a paired monitoring apparatus and console set,wherein all interfacing with the monitoring apparatus is done via theconsole and the monitoring apparatus is otherwise keyless. A variationon the Mark I is the Mark II, wherein the console is provided with a PCinterface.

A Mark III apparatus may comprise a stand-alone programmable monitoringapparatus, whereby each user of a set of multiple monitoring apparatushas no need for a console. The physiotherapist has a console which canindividually program the set of monitoring apparatus such as thetraining range sensitivity (ie. curvature limits), set the training timedosage (eg. ten minutes), set the stimulus type (eg vibration andaudio). The standalone programmable monitoring apparatus still has theability to store data of the training sessions such as time, date,number of transgressions, type of transgression and the like The data istransferred to the console when the user returns to the physiotherapistfor a progress check and/or treatment. The Mark III monitoring apparatushas one key to begin a posture training session and set the neutral ordesired posture. The posture training sessions then operate according tothe settings previously programmed into the monitoring apparatus by aconsole. The key if pressed and held down during a posture trainingsession will end the session before the automatic cessation thatotherwise would have occurred in accordance with the training timedosage.

A Mark IV apparatus may be described as a stand-alone, non programmablemonitoring apparatus. The monitoring apparatus is a stand-alone productthat does not communicate with other components and does not collectdata. The settings that are variable on the Marks I to III are preset onthe Mark IV. For example, the apparatus may be preconfigured to provideonly vibratory stimulus or some other preconfigured stimulus, and thetraining dosage may be preset to, for example, five minutes or any otherselected time. As a bare bones product, the Mark IV is the lowest costoption.

Mark V apparatus may comprise a cervical monitoring apparatus and assuch may be of a Mark I to IV type.

It will of course be realised that while the foregoing has been given byway of illustrative example of this invention, all such and othermodifications and variations thereto as would be apparent to personsskilled in the art are deemed to fall within the broad scope and ambitof this invention as defined in the claims appended hereto.

The claims defining the invention are as follows:
 1. Apparatus for theprevention and treatment of posture deficiencies including: monitoringmeans including a molded elastomeric body member having a bondingsurface whereby the body member may be adhesively secured along aselected portion of a spine of a user and encapsulating an operatingassembly comprising an elongate, resiliently flexible membercantilevered from a relatively rigid mounting portion located toward oneend of said body member, said resiliently flexible member having mountedthereon a strain gauge in a region adjacent said mounting portionwhereby strain in said resiliently flexible member produces a signalcorresponding to curvature of a portion of the spine; and output meansresponsive to said signal and adapted to generate an output indicativeof said curvature.
 2. Apparatus for the prevention and treatment ofposture deficiencies according to claim 1, wherein said selected portionof the spine is the lumbar portion.
 3. Apparatus according to claim 2,wherein said body member comprises a unitary body member secured to theselected spinal portion and said strain gauge is responsive to a directcorrespondence between the body member and the curvature of the spinalportion to which the body member is attached.
 4. Apparatus for theprevention and treatment of posture deficiencies according to claim 1,wherein said monitoring means is configured such that mechanicalreaction of the apparatus to movement of the spine of the user isminimized such that user awareness of the action of the apparatus isminimized.
 5. Apparatus for the prevention and treatment of posturedeficiencies according to claim 4, wherein said monitoring meanscontains discrete monitoring elements, and wherein interrelationshipbetween adjacent elements is monitored by optical or electronic meansand the signal generated is optical, electronic via an optical coupler,or electronic.
 6. Apparatus for the prevention and treatment of posturedeficiencies according to claim 1, wherein said signal interfaces withindicator means which is selected from one or more of vibratory stimuli,audio stimuli, electrical stimuli or a visual indication means. 7.Apparatus for the prevention and treatment of posture deficienciesaccording to claim 6, wherein said indicating means comprises anaversive indication of an adverse static or dynamic curvature toreinforce maintenance of good posture.
 8. Apparatus for the preventionand treatment of posture deficiencies according to claim 7, wherein saidaversive indication includes vibro-tactile stimulus of sub-audiblefrequency.
 9. Apparatus for the prevention and treatment of posturedeficiencies according to claim 6, wherein said indicator means isdeactivatable to permit gathering of baseline data on a curvaturefunction of the user independent of postural feedback.
 10. Apparatus forthe prevention and treatment of posture deficiencies according to claim1, wherein said adhesive securing is by means selected from one or moreof adhesive pads or tape members, adherable hook and loop fastenings, orstraps.
 11. Apparatus for the prevention and treatment of posturedeficiencies according to claim 10, wherein said bonding surface isadapted to engage skin of the user by way of an adhesive layer. 12.Apparatus for the prevention and treatment of posture deficienciesaccording to claim 11, wherein said adhesive layer comprises a medicalgrade hypoallergenic adhesive.
 13. Apparatus for the prevention andtreatment of posture deficiencies according to claim 1, wherein saidstrain gauge is selected to provide a signal in response to thecurvature of the spine as a consequence of the spine exceeding certainselected limits.
 14. Apparatus for the prevention and treatment ofposture deficiencies according to claim 1 wherein said monitoring meansprovides a continuous output across a range of positions of themonitoring means.
 15. Apparatus for the prevention and treatment ofposture deficiencies according to claim 14, wherein said elongatedresiliently flexible member comprises a strip of metal or plasticembedded in the body member.
 16. Apparatus for the prevention andtreatment of posture deficiencies according to claim 15, wherein saidmonitoring means includes a pair of strain gauges mounted on oppositefaces of said strip.
 17. Apparatus for the prevention and treatment ofposture deficiencies according to claim 16, wherein said strain gaugesoutput data to means of recording condition status on a continuous,intermittent or condition responsive basis.
 18. Apparatus for theprevention and treatment of posture deficiencies according to claim 17,wherein said strain gauges output data that is selectively used totrigger reacting means that serves to provide a condition responsivesignal to the user.
 19. Apparatus for the prevention and treatment ofposture deficiencies according to claim 18 wherein the conditionresponsive signal is selected from immediate or selectably delayedstimulus.
 20. Apparatus for the prevention and treatment of posturedeficiencies according to claim 19, wherein both condition responsiveand timed stimuli are supplied to the user, to indicate poor posture andto stimulate the user periodically for voluntary postural variety,respectively.
 21. Apparatus for the prevention and treatment of posturedeficiencies according to claim 20, wherein said strain gauges providedata to data collection means.
 22. apparatus for the prevention andtreatment of posture deficiencies according to claim 21, wherein saidcollection means includes one or more of a counter, time base record orthe like adapted to record the number and timing of stimuli applied tothe user.
 23. Apparatus for monitoring the spinal posture of a person,comprising: a substantially rigid support; a resiliently flexibleelongate member-having first and second opposed ends, said first endbeing mounted in cantilever fashion to the support; at least one straingauge mounted on the elongate member towards said first end, each straingauge being responsive to strain in the elongate member to produce asignal indicative of the level of strain; and a flexible elastomericbody member encapsulating the support, the elongate member and the atleast one strain gauge, and defining at least one major surface suitablefor contacting a body of a user along a portion of the lumbar spine. 24.Apparatus according to claim 23, further including output meansresponsive to said signal to produce an output that is a measure of thespinal posture of the user.
 25. Apparatus according to claim 23, whereinsaid at least one strain gauge comprises two strain gauges, the gaugesbeing mounted on opposite faces of the elongate member towards saidfirst end.